The invention relates to a camshaft-adjusting device with first and second camshafts and means for adjusting the phase position of the two camshafts relative to a crankshaft driving the camshafts.
In a conventional reciprocating internal combustion engine with a cylinder head including gas exchange channels and gas exchange control elements, use is made of inlet and outlet valves at the inlet side and outlet side which valves are operated by camshafts. In order to operate the internal combustion engine favorably in terms of fuel consumption and favorably in terms of engine emissions, it is known to adjust the phase position of a camshaft bearing the cams in relation to a crankshaft driving said camshaft. In an arrangement with a camshaft for the inlet valves and a camshaft for the outlet valves, it is advantageous if each of the camshafts is in each case rotatable with respect to the crankshaft. An arrangement of this type is known, for example, from the U.S. Pat. No. 5,543,383. In this case, a crankshaft drives a first camshaft for inlet valves, which camshaft in turn uses a driving means to drive a second camshaft for driving the outlet valves. An adjusting device which permits adjustment of the camshaft to a retarded or advanced position is arranged on the first camshaft. If the adjusting device is actuated and the first camshaft is changed in its phase position with respect to the crankshaft via a displaceable piston of the adjusting device, the other camshaft follows via a mechanical coupling and likewise changes its phase position in relation to the crankshaft.
It is the object of the present invention to provide a camshaft-adjusting device for two camshafts, which device is relatively small and can be manufactured cost-effectively and, in particular, is suitable for an adjusting device with a rotary actuator.